Pump for liquid foods, drugs, and liquid chemicals



Dec. 11, 1956 F. BERDELLE- HILGE ET AL PUMP FOR LIQUID FOODS, DRUGS AND LIQUID CI-IIEIIVIICALS Filed Sept. 18, 1951' 3 Sheets-Sheet J W1., l lui Dec. 11, 1956 vP. BERDELLE-HILGE ET AL 2,773,454

PUMP FORv LIQUID` FOODS, DRUGS AND LIQUID CHEMICALS Filed Sept. 18, 1951 3 Sheets-Sheet 2 Dec. 11, 1956 P. BERDELLE-HILGE ETAI. 2,773,454

PUMP FOR LIQUID FOODS, DRUGS AND LIQUID CHEMICALS Filed Sept. 18, '1951 3 Sheets-Sheet .'5

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@WMM/HM?, wf www? mmum'gmw Sm y www# MMQA United States Patent O PUMP FOR LIQUID FOODS, DRUGS, AND LIQUID CHEMICALS Philipp Berdelle-Hilge, Philipp Schreiner, Wilhelm Bless mg, and Richard Sthr, Mainz, Germany, assignors to Philipp Hilge, Mainz (Rhine), Germany, a firm Application September 18, 1951, Serial No. 247,062

4 Claims. (Cl. 103-97) This invention concerns a pumping unit for conveying liquids, especially of the food and luxury industries and of the pharmaceutical and chemical industries. Centrifugal pumps, which are assembled directly with an electric motor to form a generally transportable unit, are usually employed for these purposes. The rate of delivery or pressure at which delivery takes place has in pumps of this type to be altered at times. This has hitherto been elfected by a suitable regulation of the speed of revolution of the driving motor. Regulation of this type has disadvantages in various respects.

In place ot" a driving motor which can be regulated, there has already been provided between the motor and the pump a gearing with which various speeds of revolution of the pump can be obtained, with the speed of revolution of the motor remaining constant. As a result, however, there occur additional points of friction and wear; in addition, the total weight of the unit increases, which is disadvantageous, especially in the case of transportable pumps. i

Moreover, it is known to provide centrfugalpurnps comprising several pumping-units with rotary slides for switching the units as desired into parallel or series arrangement. These known devices have the drawback of requiring considerable space for the change-over members and their associated conduits. Also, they only permit a variation to half or double of the amounts of liquid delivered or of pressures built up.

lt is an object of the present invention to overcome these and other drawbacks of the known devices by providing a centrifugal pump comprising several pumping units capable of regulation, both as to amount of liquid deiivered and to pressure, with a constant speed of revolution of the motor and without the provision of a gearing.

It is another object of the invention to provide a pump whose design and operation are easily adapted to various locations and varying attachmennts.

The pump according to the present invention substantially comprises a cylindrical housing of unit construction containing adjoining annular sections which form fixed installation members or units of said housing, each unit comprising an impeller and two guide members therefor. An electric motor for driving the pump is disposed coaxially therewith. The liquid to be pumped is conveyed through axially disposed passages from and to two openings located at the end of the housing opposite to that at which the motor is arranged. One of the characteristics of the invention is a rotary slide member for making the change-over from parallel to series connection and conversely, which is disposed between two adjoining pump units transversely with respect to the mounting shaft of said units. The slide is, at the same time, a control member capable of adjusting the passages to different cross-sections for liquid to be pumped through.

A second control member is, furthermore, provided according to the invention, which is arranged coaxially i 2,773,454 Patented Dec. .11, 1956 with the shaft and serves for alternately connecting the openings of the housing to the suction and pressure channels, respectively.

A pump unit of this kind is also suitable for the installing of additional, identical pump members, whereby the capacity can be correspondingly increased.

The invention will be described further by Way of example, with reference to the accompanying drawings in which:

Fig. l is an external plan view of a pump unit constructed according to the invention,

Fig. 2 is a vertical longitudinal section through the pump unit on the line II-II of Fig. 1, the individual pump members being connected in parallel,

Fig. 3 is a view corresponding to Fig. 2, showing the individual pump members connected in series,

Fig. 4 is a further view corresponding to Fig. 2, showing a device for permanent parallel connection of the individual pump members,

Fig. 4a is a sectional view taken along line 4-4a of Fig. 3.

Fig. 4b is a similar sectional View as Fig. 4a but taken with the rotary slide valve in another position.

Fig. 5 is a sectional view along section line 55 of Fig. 4a.

Fig. 6 illustrates the rotary slide member in elevation.

As shown in the drawings, the Whole pump unit is contained in a closed, cylindrical external housing 1 of unit construction and comprising a plurality of adjacently disposed annular sections of identical diameter, forming individual stationary members or units of the housing 1a. The housing 1 thus composed is followed by a cylindrical body 2 of the same diameter, the outer end of which is connected by ange joints (not shown) with the housing 3 of an electric motor which serves to drive the pump.

Two impellers 5, 6 (Figs. v2 to 4) are disposed on a shaft 4 common to the centrifugal pump and its driving motor. Together with stationary guide plates 7, 8 or 9, 10 respectively, bordering them on both sides, the wheels 5, 6 each form a pump member.

Between the two pump members there is located, laterally offset from the vertical middle longitudinal axis of the pump (cf. Fig. l), a switching and regulating member constructed as a rotary slide 11, the vertical spindle 12 of which can be actuated at its top end, which projects out ofthe housing 1, by means of a hand lever 13.

On the sides of the pump members remote from each other are disposed two further stationary members 14, 1S which serve for mounting and for sealing the shaft 4, and which also provide a suction chamber 16 and a pressure chamber 17 respectively, which chambers are disposed round the shaft 4 in the shape of a ring. One of these components forms in addition the end section, which is remote from the driving side of the unit, of the pump housing, with openings 18, 19 (Fig. 5) for the inlet or discharge of the liquid being pumped. At the same end there is further provided, coaxially with the shaft 4, a second rotary member 20, which, like the rotary slide 11, is actuated from outside by means of a hand lever 21 (Fig. 2), and is so constructed that the inlet and outlet openings can be brought alternately into communication with the suction side and the pressure side of the pump.

The operation of such a switching member is known per se. Figs. 6 and 7 illustrate the functioning of a member of this type. From these figures it may be seen that member 20 upon each rotation by 90 degrees changes the communications; at one time a communication is effected between the opening 18 of the housing with the suction channel 22, shown Vat the bottom, while opening- (Fig. 6). Atother times, opening 19` connects for de` livery and opening 18 for discharge of the liquid to be the member is guided and packed in the pump housing.

The outer faces 26a and 27a of said discs are segments` of a common conical shell, the cone having an increasing diameter in the direction towards the operator. The outer faces of ,the reinforced parts of the stem 28 connecting the two discs with each other likewise lie in said conical shell.

A suction channel 22 and a pressure channel 23 located opposite each other extend parallel to the shaft and directly adjacent the interior of the wall of the pump housing. A filter 24, likewise built into the housing, is connected in front of the suction channel 22, whilst a manometer is connected to the pressure chamber, into which the pressure channel 23 opens.

The rotary slide 11 has recesses 11' and 11, respectively, on opposite sides in the upper and lower regions of the slide. Recess 11 consists of two parts separated by a bent wall member. One of these parts s open toward the top and the outside, in radial and axial direction to the slide, and is bounded by the intermediate wall at the inside, said wall cutting segments from the circular cross-sections of the slide, said segments having a radial height increasing toward the top. The other part of 11 forms a channel extending across the slide. The second recess 11" comprises only a part with U-shaped crosssection open in axial and radial direction to the slide, i. e. open toward the outside and the bottom, respectively, the cross-section likewise increasing with the distance from the shaft.

A rotary slide of this design permits to connect the two pump units 5, 7, 8, and 6, 9, 10 in parallel or series with two positions taken up by the slide when turned through 90, as shown in Figs. 2 and 3.

In the first case, the pump conveys double the quantity and in the latter case delivers at twice the pressure of each individual member. In addition to this, by providing the special shape for recesses 11 and 11", as explained above, the cross-sectional areas of the passages provided by the rotary slide can be altered as desired within the limits set by the maximum total capacity of the pump, for both types of connection, in the sense of the ability to regulate as desired the rate of delivery or the pressure at which delivery takes place. i

ln parallel connection, one part of the upper recess 11' establishes a communication between the discharge side of the pump unit 6, 9, 10 and the pressure channel 23,

. r' and the lower recess 11. connects the suction channel 22 with the intake side of pump unit 5, 7, 8 (see Fig. 2). ln series connection, the other channel-shaped part of the upper recess 11 establishes a communication between the discharge side of the one pump unit 6, 9, 10 and the intake side of the other pump unit 5, 7, 8, whereas the lower recess 11" does not make any connection at all due to the width of two parallel faces of the slide; it forms, as it were, a dead end communicating with suction channel 22 (see Fig. 3).

If the slide is turned through 180 from the position shown in Fig. 2, it cuts olf in the upper region the exit of pump unit 6, 9, 10, and in the lower region the inlet of the other unit 5, 7, 8, so that `the pump does not deliver at all.

The particular advantage of the new arrangement ac cording to the invention consists operationally in that, with an always constant number of revolutions, i. e. with the employment of a simple driving motor, which does not need to be regulated, and without a gearing which requires regulation, the capacity of the pump with regard to rate of delivery and delivery pressure can be adapted to the particular requirements. At the same time, individual pump members also do not need to be switched in or out at any time, but with each pumping member for instance half its fundamental deliveryrate or half its normal delivery pressure can be obtained, so that, with parallel connection, the two pump members together deliver at exactly the same pressure, or, with series connection, deliver the same quantity, as does otherwise one pump having only one member. No throttling or circulating of the delivery liquid takes place within the pump members, so that the disadvantages associated therewith, such as heating and effervescence of the liquid, and changes in the characteristics thereof, which is particularly undesirable in many of the kinds of liquids to be considered in this connection, such as wine, fruit juice, and spirits, are avoided.

Extremely gentle delivery of the liquids concerned, with little friction, is obtained in addition through the axial arrangement of the rotary member 20, which makes possible comparatively few deflections.

In the `embodiment shown in Fig. 4, there is disposed between the two pump members, instead of the rotary slide 11, a fixed guiding and separating wall 26 having a slight inclination to the radial direction, by means of which the pump members are permanently connected in parallel. Such a form of construction is particularly suitable when no alteration in the operating conditions has to be taken into account, or when the delivery rate is to be increased only occassionally and then to a definite extent, which is easily possible by tting a suitable number of further pump members. ln a corresponding manner, the same applies for an occasional increase of the delivery pressure by one or more additional stages with series connection.

ln addition to the operational advantages, a pump unit constructed in accordance with the invention also has advantages in manufacture. These consist principally in that no planing, but only turning, has to be carried out on the individual components. The manufacture of pumps having different capacity is also simplified by employing uniform individual parts. The enclosing cylindrical housing with the smooth outer surface at the same time gives the whole unit a pleasing appearance.

We claim:

l. A pump for use especially with liquid foods and beverages, and pharmaceutical and chemical liquids, comprising a plurality of adjoining annular sections forming an externally cylindrical housing, at least two identical pump members disposed within said housing and each comprising an impeller and two guide members therefor, an electric driving motor, and a shaft common to said pumping members and said motor, said housing having formed therein at its end opposite to that at which said driving motor is located, inlet and discharge openings for the liquid being pumped, and suction and pressure passages associated with said inlet and discharge openings respectively for guiding said liquid within the housing, a rst rotary slide, means associated with the f slide for connecting said units in parallel and series, said slide being arranged transversely with respect to the shaft and between said pump units, said slide being also capable of changing the cross-sections of the inlet passage for admission of liquid to be pumped and of the outlet passage for withdrawal thereof, and a second rotary member arranged coaxially with said shaft and being capable of alternately connecting as known per se the openings of the housing with the suction channel and the pressure channel.

2. A pump as set forth in claim l, wherein said first rotary slide is offset relative to said shaft and has two recesses formed on opposite sides with respect to its circumference and with respect to the shaft, said recesses being adapted to connect said pump units in parallel and in series, depending on the setting of said slide, one of said recesses in parallel arrangement connecting the discharge side of the one pump unit with the pressure channel, and the other recess the suction channel with the intake side of another pump unit, whereas in series connection, with said rst rotary slide being in a position turned through 90, said first recess being capable of connecting the discharge side of one pump unit with the intake side of the other pump unit and said second recess forming a dead end.

3. A pump according to claim 2, wherein said rst rotary slide has two recesses, the one of said recesses, which is capable of alternately connecting the discharge side of one pump unit with the pressure channel and with the intake side of another pump unit, containing two parts separated by a wall member, one of said parts, which is open axially and radially with respect to the slide, forming a segment-shaped part at each cross-section of the slide with an increasing radial height as its distance from the shaft increases, and said other part forming a channel extending across said slide.

4. A pump according to claim 2, wherein said second recess in said rst rotary slide, which in parallel connec- 6 tion of the pump units is capable of connecting the suction channel with the intake side of the first unit, and in series connection of all units does not make any connection, is open in axial and radial direction with respect to the slide and has a U-shaped cross-section and a depth increasing With the distance from the shaft.

References Cited in the tile of this patent UNITED STATES PATENTS 1,782,469 Havens Nov. 25, 1930 1,875,419 Claypool Sept. 6, 1932 2,282,569 Fabig May l2, 1942 FOREIGN PATENTS 17,471 Great Britain July 23, 1914 543,127 France May 27, 1922 

